1. Field of the Invention
The present invention relates to a structural design of a flexible circuit board, and in particular to a tear protection structure for a flexible circuit board.
2. The Related Arts
In each of a variety of electronic devices that are currently used, due to the amount of transmission through signal cables being increasingly large, the number of signal transmission lines is also ever increased. Among all currently employed techniques of signal transmission lines, flexible circuit boards are the most promising technique at present. The flexible circuit boards are featured for being light in weight and small in volume and are adaptable to assembling conditions for products having various outside configurations for a general purpose of increasing wire density to serve as circuit carrier for signal connection or component assembling. A flexible circuit board can be integrated or connected with active components, passive components, or modularized components and thus the flexible circuit board can also serve as a mechanical feature.
A conventional flexible circuit board is often provided with a tear protection hole formed at a location corresponding to a terminal of wiring in order to prevent the flexible circuit board from be torn off along a slit line of the flexible circuit board due to stretching, folding, extending through a bore, or even maintenance operations. In a conventional flexible circuit board, wire lay-out is generally simple and a large space that is preserved between lines is large enough to accommodate the formation of a large circular hole to serve as the tear protection hole, preventing undesired tearing along a slit line of the flexible circuit board resulting from stretching or folding.
The progress of modern technology allows for complicated wire layouts to be used in a flexible circuit board and thus, the spacing between lines is reduced. The conventional way of forming tear protection hole, which is relatively large, may get interfering with the wire layout on the flexible circuit board. Thus, it is desired to provide a solution that is applicable to a very limited space within a wire layout while helping prevent the occurrence of tear along a slit line of a flexible circuit board resulting stretching, folding, extending through a bore, or a maintenance operation. This is a challenge of researches for the manufacturers of the industry to overcome such a prior art problem.